restructure dump.c slightly to make it more flexible
WIP: progress towards serializing/deserializing a single module at a time
WIP: add support for forward value references in the backref table
WIP: rehash affected method tables due to datatype->uid changes after restoring
replace itrunc(Uint8, 1234) => mod(1234, Uint8), etc. [fix #8646]
Improving comments to clarify how indentation works.
be alot more careful about serializing types, especially ones that are also methods, and minor corrections
serialize methlist in reverse order to stabilize method order after deserializing (see #8652 for cause). note this causes more nuisance ambiguity warnings
fix #8678, reading large files on windows

read() on windows takes a uint, so apply a similar io limit per call
as done on mac (directly reusing the same code would give a compiler
warning, since long is 32 bits on windows)
Merge pull request #8689 from JuliaLang/tk/fix8678

fix #8678, reading large files on windows
doc: Remove reference to deprecated 'dense' function
Merge pull request #8691 from julian-gehring/patch-doc-dense

doc: Remove reference to deprecated 'dense' function
Better function cross-referencing for Arrays chapter
Fix #4933
Fix #8570 and add test.
itrunc => mod: a few more integer modulus methods.
add missing precompile
integer trunction: use `n % T` instead of `mod(n, T)`.
Remove non-existent `tofirst` and `tolast` methods from adjuster API in Dates docs
Add documentation for Dates types