Increase default dbcache to 100 MiB
add constants for shared (GUI/core) -dbcache settings

- adds nDefaultDbCache, nMaxDbCache and nMinDbCache in txdb.h
[Qt] small .ui cleanup for optionsdialog and coincontrol
Merge pull request #3687

82e9600 add constants for shared (GUI/core) -dbcache settings (Philip Kaufmann)
879b390 Increase default dbcache to 100 MiB (Pieter Wuille)
Merge pull request #3693

f05fa03 [Qt] small .ui cleanup for optionsdialog and coincontrol (Philip Kaufmann)
Change new constants in txdb.h to int64_t

A shift overflow was happening when using these to check against in init.cpp.
Fixes #3702.
qt: Rename 'Confirmed' balance to 'Spendable' on overview page

The word 'Spendable' more precisely says what the balance actually means.

Avoids the confirmed/unconfirmed confusion that can be caused by #3676.
Merge pull request #3699

ddcabae qt: Rename 'Confirmed' balance to 'Spendable' on overview page (Wladimir J. van der Laan)
Merge pull request #3703

ad54a9b Change new constants in txdb.h to int64_t (Wladimir J. van der Laan)