Fluent methods, especially setters, return the object on which are
called. This is documented in PHPDoc using the `$this` keyword, which
is equivalent to `static` with the additional notion of object identity.
This helps IDEs and static analysis tools provide more meaningful output.
Column indexes are always based on 1 everywhere in PhpSpreadsheet.
This is consistent with rows starting at 1, as well as Excel
function `COLUMN()`. It should also make it easier to reason about
columns and rows and remove any doubts whether a specific method is
expecting 0 based or 1 based indexes.
Fixes#273
Fixes https://github.com/PHPOffice/PHPExcel/issues/307
Fixes https://github.com/PHPOffice/PHPExcel/issues/476
Because it is a budren to maintain and LGPL 2.1 does not require
them, but only suggest them:
> To apply these terms, attach the following notices to the library.
> It is **safest** to attach them to the start of each source file
> to most effectively convey the exclusion of warranty; and each
> file **should** have at least the "copyright" line and a pointer
> to where the full notice is found.
https://www.gnu.org/licenses/old-licenses/lgpl-2.1.en.html#SEC4
Having default values made it harder for end-user to figure out whether
it the arguement had to be supplied or not. Ommitting the argument may
lead to hard to debug issues, and is overall not a good idea.
Closes#110
Because alignment was all broken and becaues it doesn't improve much
the code readability, but potentially create more complicated diff, we
prefer to unlaign all docblocks.
