Misc. Typo fixes
Both user and non-user facing. Found via `codespell -q 3  -I ../pandas-whitelist.txt` whereby the whitelist consisted of: 
```
behaviour
indicies
initialise
initialised
initialising
resetted
thru
writeable
```
thanks @luzpaz 

have a look at https://travis-ci.org/pandas-dev/pandas/jobs/322503804

couple of linting issues (now lines too long) as well as a failing test that checks the error message (you can adjust the test / message). @jreback apologies, i'm having trouble understanding the errors of the tests on TravisCI. Are all of those issues related to this PR ? Can you give me an example of lines that are too long? I'll be happy to fix, I'm not yet down with the lingo. Thank you.  ``git diff master --name-only -- "*.py" | grep "pandas" | xargs flake8``

will show the linting issues
 also you need to merge master. and there is 1 test failure as indicated. @jreback After I rebase, should I force push or just create another commit ? you can force push if you rebase, or simply ``git merge master`` and just keep pushing commits. 2nd is prob easier thanks @luzpaz nice patch! # [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/18966?src=pr&el=h1) Report
> Merging [#18966](https://codecov.io/gh/pandas-dev/pandas/pull/18966?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/58e8ee2055c09d59e9724b1eda66d9012dc73e53?src=pr&el=desc) will **decrease** coverage by `0.02%`.
> The diff coverage is `100%`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/18966/graphs/tree.svg?token=eZ4WkYLtcO&src=pr&width=650&height=150)](https://codecov.io/gh/pandas-dev/pandas/pull/18966?src=pr&el=tree)

```diff
@@            Coverage Diff             @@
##           master   #18966      +/-   ##
==========================================
- Coverage   91.57%   91.55%   -0.03%     
==========================================
  Files         150      150              
  Lines       48933    48933              
==========================================
- Hits        44812    44800      -12     
- Misses       4121     4133      +12
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `89.91% <100%> (-0.03%)` | :arrow_down: |
| #single | `41.75% <0%> (ø)` | :arrow_up: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/18966?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/core/reshape/melt.py](https://codecov.io/gh/pandas-dev/pandas/pull/18966/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvcmVzaGFwZS9tZWx0LnB5) | `97.24% <ø> (ø)` | :arrow_up: |
| [pandas/core/sparse/array.py](https://codecov.io/gh/pandas-dev/pandas/pull/18966/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvc3BhcnNlL2FycmF5LnB5) | `91.82% <ø> (ø)` | :arrow_up: |
| [pandas/io/formats/excel.py](https://codecov.io/gh/pandas-dev/pandas/pull/18966/diff?src=pr&el=tree#diff-cGFuZGFzL2lvL2Zvcm1hdHMvZXhjZWwucHk=) | `96.71% <ø> (ø)` | :arrow_up: |
| [pandas/core/dtypes/cast.py](https://codecov.io/gh/pandas-dev/pandas/pull/18966/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvZHR5cGVzL2Nhc3QucHk=) | `88.42% <ø> (ø)` | :arrow_up: |
| [pandas/core/computation/pytables.py](https://codecov.io/gh/pandas-dev/pandas/pull/18966/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvY29tcHV0YXRpb24vcHl0YWJsZXMucHk=) | `92.37% <ø> (ø)` | :arrow_up: |
| [pandas/core/algorithms.py](https://codecov.io/gh/pandas-dev/pandas/pull/18966/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvYWxnb3JpdGhtcy5weQ==) | `94.14% <ø> (ø)` | :arrow_up: |
| [pandas/tseries/holiday.py](https://codecov.io/gh/pandas-dev/pandas/pull/18966/diff?src=pr&el=tree#diff-cGFuZGFzL3RzZXJpZXMvaG9saWRheS5weQ==) | `93.1% <ø> (ø)` | :arrow_up: |
| [pandas/core/indexes/interval.py](https://codecov.io/gh/pandas-dev/pandas/pull/18966/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvaW5kZXhlcy9pbnRlcnZhbC5weQ==) | `92.61% <ø> (ø)` | :arrow_up: |
| [pandas/core/indexing.py](https://codecov.io/gh/pandas-dev/pandas/pull/18966/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvaW5kZXhpbmcucHk=) | `92.81% <ø> (ø)` | :arrow_up: |
| [pandas/io/formats/console.py](https://codecov.io/gh/pandas-dev/pandas/pull/18966/diff?src=pr&el=tree#diff-cGFuZGFzL2lvL2Zvcm1hdHMvY29uc29sZS5weQ==) | `69.69% <ø> (ø)` | :arrow_up: |
| ... and [38 more](https://codecov.io/gh/pandas-dev/pandas/pull/18966/diff?src=pr&el=tree-more) | |

------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/18966?src=pr&el=continue).
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> `Δ = absolute <relative> (impact)`, `ø = not affected`, `? = missing data`
> Powered by [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/18966?src=pr&el=footer). Last update [58e8ee2...414ee94](https://codecov.io/gh/pandas-dev/pandas/pull/18966?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
